package com.hmdp.service.impl;

import cn.hutool.core.util.BooleanUtil;
import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONObject;
import cn.hutool.json.JSONUtil;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.hmdp.dto.Result;
import com.hmdp.entity.Shop;
import com.hmdp.mapper.ShopMapper;
import com.hmdp.service.IShopService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.CacheClient;
import com.hmdp.utils.RedisData;
import com.hmdp.utils.SystemConstants;
import org.springframework.data.geo.Distance;
import org.springframework.data.geo.GeoResults;
import org.springframework.data.redis.connection.RedisGeoCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.domain.geo.GeoReference;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;

import static com.hmdp.utils.RedisConstants.*;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class ShopServiceImpl extends ServiceImpl<ShopMapper, Shop> implements IShopService {
@Resource
private StringRedisTemplate stringRedisTemplate;
@Resource
private CacheClient cacheClient;
    @Override
    public Result queryById(Long id) {
        Shop shop = cacheClient.quertWithThrough(CACHE_SHOP_KEY, id, Shop.class, this::getById, CACHE_SHOP_TTL, TimeUnit.MINUTES);
        if (shop == null) {
            return Result.fail("店铺不存在");
        }
        return Result.ok(shop);
    }
//    private static final ExecutorService CACHE_REBUILD_EXECUTOR= Executors.newFixedThreadPool(10);
    //逻辑过期解决缓存击穿
//    public Shop quertWithLogicalExpire(Long  id){
//        String shopJSON = stringRedisTemplate.opsForValue().get(CACHE_SHOP_KEY + id);
//        if (StrUtil.isBlank(shopJSON)) {
//            return null;
//        }
//        RedisData redisData = JSONUtil.toBean(shopJSON, RedisData.class);
//        JSONObject data = (JSONObject) redisData.getData();
//        Shop shop = JSONUtil.toBean(data, Shop.class);
//        if (redisData.getExpireTime().isAfter(LocalDateTime.now())) {
//            return shop;
//        }
//        String LockKey = LOCK_SHOP_KEY + id;
//        boolean islock = lock(LockKey);
//        if (islock) {
//            CACHE_REBUILD_EXECUTOR.submit(() -> {
//                try {
//                    this.saveShopToRedis(id, 20L);
//                } catch (Exception e) {
//                    throw new RuntimeException(e);
//                }
//                finally {
//                    unlock(LockKey);
//                }
//            });
//        }
//        return shop;
//    }
    //互斥锁解决缓存击穿
//    public Shop quertWithMutex(Long  id){
//        String shopJSON = stringRedisTemplate.opsForValue().get(CACHE_SHOP_KEY + id);
//        if (StrUtil.isNotBlank(shopJSON)) {
//            Shop shop = JSONUtil.toBean(shopJSON, Shop.class);
//            return shop;
//        }
//        if (shopJSON != null) {
//            return null;
//        }
//        String LockKey = LOCK_SHOP_KEY + id;
//        Shop shop = null;
//        try {
//            Boolean isLock = lock(LockKey);
//            if (!isLock) {
//                Thread.sleep(50);
//                return quertWithMutex(id);
//            }
//            //根据id数据库查询
//            shop = this.getById(id);
//            if (shop == null) {
//                //将空值写入redis
//                stringRedisTemplate.opsForValue().set(CACHE_SHOP_KEY + id, "", CACHE_NULL_TTL, TimeUnit.MINUTES);
//                return null;
//            }
//            stringRedisTemplate.opsForValue().set(CACHE_SHOP_KEY + id, JSONUtil.toJsonStr(shop), CACHE_SHOP_TTL, TimeUnit.MINUTES);
//        } catch (InterruptedException e) {
//            throw new RuntimeException(e);
//        }
//        finally {
//            unlock(LockKey);
//        }
//        return shop;
//    }

    /*public Shop quertWithThrough(Long  id){
        String shopJSON = stringRedisTemplate.opsForValue().get(CACHE_SHOP_KEY + id);
        if (StrUtil.isNotBlank(shopJSON)) {
            Shop shop = JSONUtil.toBean(shopJSON, Shop.class);
            return shop;
        }
        if (shopJSON != null) {
            return null;
        }
        //根据id数据库查询
        Shop shop = this.getById(id);
        if (shop == null) {
            //将空值写入redis
            stringRedisTemplate.opsForValue().set(CACHE_SHOP_KEY + id, "", CACHE_NULL_TTL, java.util.concurrent.TimeUnit.MINUTES);
            return null;
        }
        stringRedisTemplate.opsForValue().set(CACHE_SHOP_KEY + id, JSONUtil.toJsonStr(shop), CACHE_SHOP_TTL, java.util.concurrent.TimeUnit.MINUTES);
        return shop ;
    }*/

    @Override
    public Result updata(Shop shop) {
        if (shop.getId() == null){
            return Result.fail("店铺id不能为空");
        }
        this.updateById(shop);
        stringRedisTemplate.delete(CACHE_SHOP_KEY + shop.getId());
        return Result.ok();
    }

    @Override
    public Result queryShopByType(Integer typeId, Integer current, Double x, Double y) {
        //判断是否需要根据坐标查询
        if (x == null || y == null) {
            Page<Shop> page = query()
                    .eq("type_id", typeId)
                    .page(new Page<>(current, SystemConstants.DEFAULT_PAGE_SIZE));
            return Result.ok(page.getRecords());
        }
        int form = (current - 1) * SystemConstants.DEFAULT_PAGE_SIZE;
        int end = current * SystemConstants.DEFAULT_PAGE_SIZE;
        String key = SHOP_GEO_KEY + typeId;
        GeoResults<RedisGeoCommands.GeoLocation<String>> results = stringRedisTemplate.opsForGeo().search(key, GeoReference.fromCoordinate(x, y), new Distance(5000),
                RedisGeoCommands.GeoSearchCommandArgs.newGeoSearchArgs().includeDistance().limit(end));
        if (results == null) {
            return Result.ok();
        }
        List<Long> ids = new ArrayList<>(results.getContent().size());
        Map<String, Distance> distanceMap = new HashMap<>(results.getContent().size());
        results.getContent().stream()
                .skip(form)
                .forEach(result -> {
                    String shopIdStr = result.getContent().getName();
                    ids.add(Long.valueOf(shopIdStr));
                    Distance distance = result.getDistance();
                    distanceMap.put(shopIdStr, distance);
                });
        if (ids.isEmpty()){
            return Result.ok();
        }
        List<Shop> shops = query().in("id", ids).last("ORDER BY FIELD(id," + StrUtil.join(",", ids) + ")").list();
        for (Shop shop : shops) {
            shop.setDistance(distanceMap.get(shop.getId().toString()).getValue());
        }
        return Result.ok(shops);
    }

    //    private boolean lock(String key) {
//        Boolean flag = stringRedisTemplate.opsForValue().setIfAbsent(key, "1", LOCK_SHOP_TTL, TimeUnit.SECONDS);
//        return BooleanUtil.isTrue(flag);
//    }
//    private void unlock(String key) {
//        stringRedisTemplate.delete(LOCK_SHOP_KEY + key);
//    }
    public void saveShopToRedis(Long id, Long expireSeconds) {
        RedisData redisData = new RedisData();
        redisData.setData(this.getById(id));
        redisData.setExpireTime(LocalDateTime.now().plusSeconds(expireSeconds));
        stringRedisTemplate.opsForValue().set(CACHE_SHOP_KEY + id, JSONUtil.toJsonStr(redisData));
    }
}
